Coronavirus: Reactions to hair dyes and rashes raise questions about impact of COVID-19 on immune system

TORONTO – It appears like a rash, almost like an allergic reaction or a really bad sunburn. For Josée Laroche, this is one of the many life-changing symptoms she has struggled with since contracting COVID-19 over a year ago. For a woman named Gemma, it was an unexpected reaction to hair dye.

Skin sensitivities or allergies that appear to be linked to COVID-19 have been documented since the early days of the pandemic, adding to questions about the disease’s impact on the immune system.

“We don’t have all the data yet to really know… this needs more study – I think we’re really limited in our conclusions,” Dr Jeff Donovan, a dermatologist with the Canadian Dermatology Association and a clinical instructor in the Department of Dermatology and Skin Science at the University of British Columbia, told in a telephone interview. The most common post-COVID-19 problem he faces is hair loss.

“There are definitely a lot of post-COVID issues that we are investigating… Problems with skin reactions and other issues are prevalent. They haven’t been well mapped yet in terms of how much more common than the general population? But there is no doubt that COVID-19, the SARS-CoV-2 virus does really boost the immune system. “


The problem of skin sensitivity specifically involving hair dyeing first gained public attention recently when a British woman shared her story with the BBC. The woman, identified as Gemma, suffered burns as a result of a “patch test” performed by her hairstylist, although she said she has used the same dye for the past decade.

“The next day I felt a very hot burning sensation behind my ear, which gradually got worse to the point where it had taken on layers of skin behind my ear,” Gemma told the BBC.

Patch testing is a process where a small amount of the coloring solution is dabbed onto an inconspicuous area, such as behind the ear 48 hours before you dye your hair. That’s standard advice in most hair dye products, but it’s a step that is often overlooked, according to Donovan.

A reaction to hair dyes can be very varied, ranging from an uncomfortable rash to a very serious anaphylactic reaction, he explained. Most will have reactions that affect the face, including severe swelling, redness, and sometimes inflammation and redness of the neck. The scalp is often affected as well, with patients itching, burning, redness, stinging, and peeling.

“It’s absolutely a miserable experience for so many people,” Donovan said.

The National Hair and Beauty Federation (NHBF), the largest association of its kind in the UK posted a reminder to members on the importance of conducting allergy alert and skin sensitivity tests after the blockages have been lifted.

“I was reading and seeing a lot of reports from stylists and salon owners that people had these new reactions that didn’t have them before, so it really alerted me – something is going on here,” Stacey, hairstylist at Gemma, the British newspaper said. She said other customers have experienced a similar issue, so this was not an isolated incident.

With millions of people around the world coloring their hair multiple times a year, however, the handful of reported incidents remain small and difficult to assess without further study. Some scientists are studying how the virus could reprogram itself our body’s immune response. Although very little is known about this specific problem, Donovan said the scenario documented in the UK is “certainly possible”.

A member survey published by BeautyCouncil following a query by found that among 71 respondents who responded to the survey, 10 said customers had an unexpected allergic reaction to hair color this past. year. Of those, three said the customer had already contracted COVID-19.

“Fortunately, we have not received any reports of serious allergic reactions in customers. We strongly encourage all customers who have contracted COVID-19 to request a 48 hour patch test just to be on the safe side,” said Greg Robins , Executive Director of BeautyCouncil. , also known as the Cosmetology Association Western Canada, an association of professionals in hair salons, spas and barbers based in British Columbia.

“Additionally, in cases where a client has been vaccinated and may be prone to allergies, we encourage a 48 hour patch test.”

Robins shared some of the member’s comments, noting that there was no clear pattern. A member who has been a colourist for 35 years said the virus had not caused any adverse skin reactions in clients, while others spoke of their own experiences.

“My mom and I had COVID-19. After COVID, we both colored our hair and had weird reactions: My mom’s didn’t take the color correctly and her hair fell out like crazy. mine became the clearest they had ever been and lost its color very quickly, “wrote one member.

Some have reported reactions to the hair dye after vaccination, but not because of the infection itself.

“I have had four clients who were vaccinated had severe reactions to hair color after their second dose, but none to have COVID-19,” another member shared.

Robins pointed out that these were anecdotes. “There are always other factors involved, but for anyone who’s been doing their hair for a while, you kind of see an anomaly pretty quickly. Especially with hair color, because hair color is sort of an exact science. When it fails, it can fail quite badly.

Although there has been little documentation on this issue, Donovan says it is still important to educate hairdressers, doctors and the public, in order to better understand what may be going on.

“It can prove it’s a small number, it can prove it’s a bigger number, but that’s how very good sightings come to life,” he said.

“Last month it might have been a stubborn, itchy rash, but next month could be facial swelling and hospitalization. So we have to take it seriously.”


It has been a long and difficult year for Josée Laroche, 53, who tested positive for COVID-19 at the end of September 2020. As a long-haul, she is already struggling with serious heart problems, exhausting, severe, neurological symptoms and his doctor. thinks she may also have developed diabetes. But in addition to these health issues, she had to deal with recurring rashes on her face, arms, and legs.

“Most of the time, the rash is very itchy and very hot to the touch. The other day it happened and my face was completely red, very, very hot, very uncomfortable, ”Laroche told in a phone interview. -a long-term care home where she worked as a personal support worker, she said.

Her rash appeared within the first month after contracting COVID-19 and has continued to erupt once or twice every two weeks or so since, each time without a signal or warning, Laroche said. And last summer, she found out that she couldn’t be in the sun at all. Her skin broke out in a severe rash that looked like a really bad sunburn despite wearing a shawl, she added.

“I saw the blisters on my arm and it was so painful. So this one lasted a few days. It was pretty bad.” Bad enough for Laroche to spend the whole summer indoors and avoid the sun as much as possible when she has to go out.


Sometimes it can be difficult to determine the reactions because there may be a delay between the onset of the reaction and its cause, Donovan noted. And for many reported skin reactions, “allergy” is often used as a catch-all term, although it could be skin irritation or sensitivity, he added.

When it comes to products like hair dyes, a dermatologist will apply a very small amount of the chemical to the patient and leave it there for 48 hours. If the stain develops a red, scaly appearance, it’s a true allergic reaction, Donovan said.

If a reaction is irritating, the product may cause redness and flaking, but will set in very quickly once the product is removed.

“If the reaction continues to rumble even after the chemical is gone … What you observe over the next few days is that the redness increases and intensifies, the scaling and inflammation intensifies even though the product. chemical has been washed out – it’s a real allergy. “

Laroche says she had heard stories from other members of her Facebook group for long-haul COVID-19 who had issues when they went to get their hair dyed and decided not to proceed on her own after her infection.

“I wasn’t sure what was happening to me… I’ve seen a lot of women who have problems when they go to dye their hair, so I’m glad I never tried to do it myself. I have enough problems right now, “she said.

For Laroche, this has been a “really bad roller coaster ride” over the past year. She went from 40 hours a week to being bedridden most days due to severe exhaustion.

“My life has completely changed… Even today, I am in shock. It’s almost unbelievable that a single virus can cause all of this, ”Laroche said.

“I had the worst of the COVID virus without being intubated in the hospital.”